044 bogging

[highsiera]

Evvening all, just finished a rebuild on an older 44, and having a bit of trouble.

new seals, gaskets, rings. honed the jug, posiston was fine. even cracked the case to replace the main case gasket.

saw starts and runs in the hot start position, but runs like it's bogging down.Never gets to that sweet wide open throttle sound. clicking the trigger off to the run position kills the saw and sends a spray/ mist of fuel out the carb.
Have messed with the carb settings, swapped carbs, re-adjusted the coil position. no bar/chain etc.. but it's like it's bogging. even removed the sprocket to see it was hanging up on the brake. no luck.

have the muffler cover off, no marks on the piston so I'm doubting the crank is bad.

please help, what am I missing?? I've done a few of these, so I'm no stranger.

Please help. B

 

[BloodOnTheIce]

I'm having a similar problem, i think I have the needle in the carb adjusted too far out and it's flooding.

 

[Lakeside53]

What's your compression?

 

[highsiera]

044

sorry, should have been more explicit.

crankcase pressure tested to 20 psi.
carb was rebuilt with a kit, adjust screws removed, passages shot out w/ carb cleaner
new tank filter
h and l jets ajusted at 1 turn out
no compression tester.

talk to me about timing, spacing the coil from the flywheel with an index card

and compression, too high or too low to cause fuel spit backZ?

All good questions, thank you

 

[Lakeside53]

Spitback is usually a worn pistion skirt. All saws spit some back...
20psi is way too much.. 10 psi max or you can damage the seals. What about vacuum?

Coil - space with a business card (8 thou). If the keyway is lined up with the woodruff key in the crank... the timing is set.

 

[OilHead]

Pull off the fuel filter & see if it still does it.

 

[highsiera]

I will re-space the coil with a business card.

fuel filter is new

worn piston skirt, interesting.
Andy, would the worn skirt cause a "slap" of sorts?

The spitback at times was nearly a backfire if you will.

thanks for the tip, in the future, I'll drop the psi back to 10. I only have an old mighty vac, presuure only, no vacuum

 

[highsiera]

oh and yes, woodruff key is lined up.
used stihl tools for the difficult stuff, so nothing got bodgered up.

 

[Lakeside53]

I will re-space the coil with a business card.

fuel filter is new

worn piston skirt, interesting.
Andy, would the worn skirt cause a "slap" of sorts?

The spitback at times was nearly a backfire if you will.

thanks for the tip, in the future, I'll drop the psi back to 10. I only have an old mighty vac, presuure only, no vacuum

You say you swapped carbs -was it a "known to be good" carb? Do both spit back?


"backfire" is ignition or ignition timing. Carb spray is inlet pressure pulse that get worse as the piston wears. Yes, a bad one will slap.

 

[Lakeside53]

Swap ignitions (common 0000 400 1300) or mark TDC and 27 degrees before TDC, and put a timing light on it.


The 044 coil is "dumb" (no retard/advance). They normally fail dead or weak - timing is usually the same.. usually...

 

[highsiera]

known good carb off of my 046
same spit back on both
will swap ignitions and try agtain tomorrow.
if that fails, I'll repiston.

will report back.

Thanks again

 

[Lakeside53]

The 046 doesn't use the same ignition as the 044...
The 046 carb will run very rich on the 044...

Unless your piston is really bad, that's not your "bogging" problem, but do get a compression guage.

 

[highsiera]

thanks Andy.

I borrow the parts from my other 044

and I'll get a compression gauge from napa on my home.

I'll have to post a pic of the shop built case splitter I built modelled after your fancy Stihl push cylinder.